Compositionally Diverse Bedrock

Regolith, particulate fragmented rock and fine grained soils, generally covers most of the surface of Mars. Mantles of rocky dust often mute the landscape, filling in topographic lows and burying boulders. Sorted sand-sized soil grains are often evident in images in the form of sand dunes and ripples.

Clean exposures of bedrock are relatively rare. Fractured basement rock is sometimes visible between dunes . Sedimentary layers can also become eroded showing alternating bands, these visible bands manifesting from changes in rock strength between layers.The edges of scarps may also exhibit significant strength against erosion or large blocks and boulders at the base of the scarps. All of these examples are visible within this geologically rich image.

The abundance of rock exposures and relative scarcity of a obscuring soil layer make this region a good location to examine the compositional diversity of the parent bedrock.

Written by: Mike Mellon (audio by Tre Gibbs)   (7 November 2012)

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Image: NASA/JPL/University of Arizona